Various techniques were and are being developed for facilitating wireless communication. One of these techniques is known as Code Division Multiple Access (CDMA). CDMA receivers and transmitters utilize pseudo-random (PN) sequences to spread and de-spread the channel data. This imposes strict timing constraints on the reception process.
Receivers and transmitters can utilize a combination of transmission and reception techniques. A commonly used combination includes CMDA and Time Division Multiplex (TDM). In such a combination CDMA frames include multiple slots. Each slot can be allocated for a certain communication channel out of multiple communication channels.
Due to the multi-path effect in the propagation environment, the receiver receives several replicas (branches) of the CDMA frame. These branches are time shifted in relation to each other. A typical CDMA receiver allocates a rake finger per branch. These rake fingers should be synchronized to each other and to the beginning of the CDMA frame at each branch. U.S. Pat. No. 6,618,434 of Heidari-Bateni et al. titled “Adaptive, multi-mode rake receiver for dynamic search and multipath reception”, which is incorporated herein by reference, illustrates a prior art CDMA receiver.
There is a need to provide efficient methods and devices for processing CDMA signals.